presentation to Repsol by MYS on 9/13/06 Well Completion Design for Tight-Gas Formations M. Y. Soliman, PhD September 20, 2006 Mendoza, Argentina

presentation to Repsol by MYS on 9/13/06 Completion of Tight gas sand Various completion options Fluid Flow GeoMechanics

presentation to Repsol by MYS on 9/13/06

Successful Completion Optimization Set up realistic expectations Consider various completion options

presentation to Repsol by MYS on 9/13/06 Successful Completion Optimization Set up realistic expectations –Reservoir Characterization Well tests, Logging, and core data production analysis of offset well Stress field –Understanding of reservoir fluid properties –Realistic modeling

presentation to Repsol by MYS on 9/13/06 Successful Completion Optimization Optimize completion –Various completion strategy –Set optimization criterion or criteria –Define parameters that affect the optimum design Fracture geometry, conductivity, height Reservoir properties –Realistic modeling

presentation to Repsol by MYS on 9/13/06 Some of the Possible completion types Vertical well Fractured vertical well MLT –Radially distributed, kicked off in the middle of the formation –Vertical distribution Fractured horizontal well

presentation to Repsol by MYS on 9/13/06

Investigated properties Permeability 0.005, 0.05, 0.1 md Height 400 ft, also looked at 100 and 20 ft Pressure 4000 psi Fracture Parameters –half length 400 ft, Conductivity, 1750 md-ft MLT –6 arms 550 ft each + the vertical well Horizontal well, –1320 ft –Four fractures

presentation to Repsol by MYS on 9/13/06 Effect of completion type

presentation to Repsol by MYS on 9/13/06 Effect of completion type

presentation to Repsol by MYS on 9/13/06 Effect of completion type

presentation to Repsol by MYS on 9/13/06 Vertical Well Pressure Distribution

presentation to Repsol by MYS on 9/13/06 Fractured Vertical Well pressure Distribution

presentation to Repsol by MYS on 9/13/06 MLT pressure Distribution

presentation to Repsol by MYS on 9/13/06 Cross section

presentation to Repsol by MYS on 9/13/06 Frac HW pressure Distribution

presentation to Repsol by MYS on 9/13/06 Refrac and multiple Fractures One fracture Two perpendicular fractures Multiple fractures.

presentation to Repsol by MYS on 9/13/06

One-Frac case

presentation to Repsol by MYS on 9/13/06 Two-Frac case

presentation to Repsol by MYS on 9/13/06 GeoMechanics effect Depletion Stress interference

presentation to Repsol by MYS on 9/13/06 Effect of pressure dependant permeability and porosity

presentation to Repsol by MYS on 9/13/06 Stress Interference in Fractured Horizontal Well

presentation to Repsol by MYS on 9/13/06 Annulus Pressure, Tubing Rate, & Annulus Rate 7/10/ :0010:0011:0012:0013:0014:0015:0016:0017:00 7/10/ :00 Time A (psi) C (bpm) Annulus Pressure (psi)Slurry Rate (bpm)Flowback Rate (bpm)ACC

presentation to Repsol by MYS on 9/13/06 Conclusions The lower the permeability, the more attractive fracturing. Fracturing horizontal wells is the most promising technique in thick, tight gas formations. The geomechanics effect on complex reservoir performance should always be considered, especially when creating multiple fractures in horizontal wells Multiple fracturing from a wellbore is a fast growing area of technology